In what is believed to be one of Australia's worst beaching events, at least 90 pilot whales have died and nearly 200 are stranded at Macquarie Harbour on Tasmania's west coast.
Of the 270 whales stranded off Tasmania, marine rescue teams were able to save 25 of the animals on Tuesday, September 22, and are trying to escort more back into the sea.
On Monday, the pilot whales were discovered in shallow waters off the west coast of the island and it is unknown what brought the animals to the shore.
According to a report by The Guardian, Dr Kris Carlyon, Parks and Wildlife Services marine biologist said that the rescue operation could take a number of days.
"We don't really know how long this rescue is going to take. This morning's phase will be critical in determining what is possible and then we'll have to deal with other factors like weather, like tides and all that will come into it," he said.
"We're going to trial a couple of things this morning. We're going to refloat several animals and assess behaviour. So this entire operation … depends on how these animals respond once they've got water underneath them and are free-floating," Carlyon added.
According to the state's Department of Primary Industries, Parks, Water and Environment, Tasmania is the only Australia state where mass strandings of whales and dolphins occur regularly. While Macquarie Harbour is known for marooning of marine animals, one of this size is believed to be the worst in over a decade.
"This is a really challenging event. In terms of mass strandings in Tasmania, this is up there among the trickiest we've ever had to deal with," Carlyon was quoted as saying by CNN.
In the rescue operations involving around 40 trainers, the rescuers found three groups of whales across Macquarie Heads late on Monday. While around 200 whales had washed up on a sandbar near a boat ramp, around 30 others were found several hundred metres away. In addition, another 30 were found further inland along Ocean Beach.
The long-finned pilot whales can grow up to seven metres long and weigh up to three tonnes.
The rescuers began to re-float" a small number of whales on Tuesday morning with the help of equipments to push the animals off a sandbar into deeper waters.
"Normally we're dealing with animals high and dry on the beach. This is different. We've got animals semi-buoyant so it probably won't take too much to re-float them - just involves a bit of grunt," Carlyon was quoted as saying by BBC.
Once the whales are doing well in the water, the rescuers have to get them further out. However, due to the strong tide, this could be a challenge and boats might have to be used for the manoeuvre, Carlyon said.
Furthermore, many of the whales may be too big or could be in an unsuitable location.
"Some animals may be simply too big or in an unsuitable location," Carlyon said.
Carlyon added that to start with, the team would take the animals with the best chance of survival. Some of the whales closer to deeper waters have been guided out.
He further said that, from previous missions, the rescuers know that these whales can survive three or four days being beached. He added that many whales in this group were in good "wet and cool" conditions.
"These are long fin pilot whales, they're quite a robust species … Given that they're wet, they're cool, we got some really suitable weather actually, it's pretty ugly out there for people on the ground, but as far as the whales go, it's ideal. If the conditions stay the same, they can survive for quite a few days," Carlyon said.
Nic Deka, incident controller from the Tasmanian Department of Primary Industry, Parks, Water and Environment, said the rescue team has been taking the help of the local fish farmers.
"They have been generous enough to provide some boats and equipment and some personnel. So we'll be taking advantage of that and working with them," Deka said.
"At the present time, we have about 40 staff from across the area in Strahan. We also have some people from other departments, we have police assisting us. We got some folk from the fish farm assisting us and also a handful of volunteers," he added.
Officials have urged the public to keep away from the site, stating that they have enough helpers.
Once the rescuers save the remaining whales, they will have to move dozens of whale carcasses from inside the harbour out to sea.
Usually, during stranding, while experts prefer to leave the bodies, Carlyon said that it was not viable in this case as the area is too close to human campgrounds and activity sites.
The last mass stranding was recorded in Tasmania in 2009 when 200 whales got stranded in the beach. According to scientists, the reason for beaching is unknown.
Every year, different kinds of whale around Australia and New Zealand make seasonal migrations in pods as large as a 1,000 animals.
According to researchers, the animals follow a leader and due to their strong social bonds, the whole group often end up beaching themselves as they may hear the leader's call and follow.
"It might have been a single misadventure by one or two of them and because pilot whales are such a social species, that may have drawn the other animals in," Carlyon said.
Whales also tend to gather around an injured or distressed whale.
"Their social groups and strong bonding between the groups causes often all of them to strand," Olaf Meynecke, a whale researcher and Project Manager of whales and climate at Griffith University, told Reuters.
In 2018, over 200 pilot whales died in a week's time in New Zealand, in separate strandings off the country's east coast. In pictures of the incident that surfaced online, dozens of whales were seen stranded on an idyllic beach in a remote part of the country.